In the testing of electronic equipment containing a number of circuit boards including integrated circuits mounted in DIP's it is desirable to make test connections to the various terminals of the DIP's. In many cases it is best to test the electrical circuits while they are operating. Normally, circuit boards are removed from their normal operating environment and connected to a conventional extender board and connections are made to the DIP terminals using a conventional test probe or clip. In some cases, especially those involving high-frequency signals, the use of an extender board may introduce electrical interference into the circuit; thereby unacceptably altering the electrical characteristics of the circuit under test.